Water cutoff tester for grommets

ABSTRACT

An apparatus for testing a waterproof state of a sub insertion portion of a grommet provided in eccentric with a main insertion portion. The apparatus is provided with an enclosure for sealably enclosing an end portion of the sub insertion portion, an air feeder for feeding air for testing to a space in which the sub insertion portion is sealably accommodated, and a judging apparatus for judging whether the sub insertion portion is in a good waterproof state based on a status of the air fed from the air feeder.

TECHNICAL FIELD

This invention relates to a waterproof testing apparatus for a grommet.

BACKGROUND ART

FIG. 7 is a plan view of a known grommet of which a waterproof state istested with use of an apparatus according to this invention.

The grommet 1 shown in FIG. 7 is arranged at a certain position on atube 2 for inserting a wire harness. The grommet 1 has a flange portion3 fittingly mounted in an insertion hole of a partition wall of avehicle body. The flange portion 3 has a main insertion portion 3 a at agenerally middle part thereof for passing a primary trunk part of thewire harness, and a small-diametrical sub insertion portion 4 at aposition radially away from the main insertion portion 3 a in eccentrictherewith. The sub insertion portion 4 includes a boss portion 5 forpassing a relatively small number of wirings W in a bundle.

FIG. 8 is a cross sectional view showing a state that the sub insertionportion 4 of the grommet shown in FIG. 7 is being fastened.

As shown in FIG. 8, a polyurethane sheet 6 is wound around the outercircumferential surface of the wiring bundle W with an end portionthereof accommodated in a space between the wirings in order to securesealability between the inner peripheral surface of the sub insertionportion 4 and the wiring bundle W. A clamp belt 7 wound around the outerperipheral surface of the boss portion 5 is pulled in the direction ofarrow A in FIG. 8 to fasten the boss portion 5. Thus, a waterproof stateof the grommet is secured.

Heretofore, there has been proposed an apparatus for testing awaterproof state of the main insertion portion of the grommet 1.However, an apparatus for checking whether the sub insertion portion 4has a waterproof structure has not been put into practice so far.

In view of the above, it is an object of this invention to provide awaterproof testing apparatus for a grommet capable of easily andaccurately testing whether a sub insertion portion provided in eccentricwith a main insertion portion of the grommet has a waterproof structure.

DISCLOSURE OF THE INVENTION

To accomplish the above object, this invention is directed to anapparatus capable of easily and accurately testing whether a subinsertion portion of a grommet is in a good waterproof state, in whichthe grommet is provided with a flange portion mountable on a vehiclebody, a main insertion portion formed on the flange portion forinserting a bundle of wirings, and the sub insertion portion provided ineccentric with the main insertion portion.

The testing apparatus according to an aspect of this invention comprisesenclosing means which sealably encloses an end portion of the subinsertion portion, air feeding means which feeds air for testing to aspace of the enclosing means in which the sub insertion portion issealably accommodated, and judging means which judges a waterproof stateof the sub insertion portion based on a status of the air fed by the airfeeding means.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view schematically showing an entireconstruction of a waterproof testing apparatus in accordance with anembodiment of this invention;

FIG. 2 is an enlarged perspective view showing essential parts of theapparatus shown in FIG. 1;

FIG. 3 is a partially plan view illustrating a testing procedureimplemented by the apparatus in accordance with the embodiment shown inFIG. 1;

FIG. 4 is a partially plan view illustrating the testing procedureimplemented by the apparatus in accordance with the embodiment shown inFIG. 1;

FIG. 5 is an enlarged sectional view showing essential parts of theapparatus in accordance with the embodiment shown in FIG. 1 in testing;

FIG. 6 is a partially sectional view of a modified part of the apparatusin accordance with the embodiment of this invention;

FIG. 7 is a schematic plan view of a grommet of which a test on awaterproof state is implemented;

FIG. 8 is a sectional view showing a state that a sub insertion portionof the grommet shown in FIG. 7 is being fastened:

FIG. 9 is a perspective view showing a modification of enclosing meansin the apparatus in accordance with the embodiment of this invention;

FIG. 10 is a perspective view showing a manner as to how the subinsertion portion of the grommet is mounted to the enclosing means shownin FIG. 9;

FIG. 11 is an enlarged sectional view showing essential parts of theenclosing means shown in FIG. 9 in testing;

FIGS. 12A and 12B are sectional views radially sectioned each showingthat a pipe of the enclosing means shown in FIG. 9 is radially andresiliently deformed to openably dose a slit, wherein (a) shows a statethat the slit is opened, and (b) shows a state that the slit is closed;and

FIG. 13 is a perspective view illustrating a modification of theenclosing means shown in FIG. 9 including a pipe and a pipe holder.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, a preferred embodiment of the invention is described indetail with reference to the accompanying drawings.

FIG. 1 is a perspective view schematically showing an entireconstruction of a waterproof testing apparatus 10 for a grommet inaccordance with an embodiment of this invention. FIG. 2 is an enlargedperspective view showing essential parts of the apparatus shown in FIG.1.

Referring to FIGS. 1 and 2, the testing apparatus 10 in accordance withthe embodiment of this invention is described. The apparatus 10comprises a sealing unit 20 as enclosing means for sealably enclosing anend portion (corresponding to the end portion of the boss portion 5 inFIG. 7) of a sub insertion portion 4 of a grommet 1 substantiallyequivalent to the grommet shown in FIGS. 7 and 8, and an air checker 40for checking a waterproof state of the sub insertion portion 4 byfeeding air for testing the sealing unit 20.

The sealing unit 20 includes a rectangular plate-like base 21 in planview, a pipe holder 22 fixedly supported at an end portion on the uppersurface of the base 21, an encasing tube 23 which selectively movestoward and away from the pipe holder 22 on the base 21, and an operationmechanism 30 as operation means for drivingly moving the encasing tube23.

The base 21 is a sheet metal member of a relatively large thickness andhas a generally rectangular shape in plan view. It should be noted that,throughout this specification, a longitudinally end portion of the base21 (the side where the pipe holder 22 is mounted) is defined as a frontside of the apparatus.

Referring to FIG. 2, the pipe holder 22 is described. The pipe holder 22is a block member made of a resin. The pipe holder 22 has an uprightposition and is provided transversely in the middle part of the base 21at a frontal end portion thereof. A groove (housing portion) 22 a isformed in an upper part of the pipe holder 22. A pipe 24 is detachablymounted in the housing portion 22 a. The pipe 24 is, for example, ahollow cylinder made of e.g., brass. As will be described later, thepipe 24 has such a construction as to allow a bundle of wirings Winserted in the sub insertion portion 4 of the grommet 1 to pass and topress the circumference of the sub insertion portion 4 from a sideopposite to the side where the boss portion 5 of the sub insertionportion 4 is formed. A shoulder part 22 b against which a frontalsurface of the pipe 24 is abutted is formed at a front end of thehousing portion 22 a to keep the pipe 24 from disengaging from the pipeholder 22.

Next, the arrangement of the encasing tube 23 is described withreference to FIG. 1. The encasing tube 23 is a cylindrical member and isconcentrically connectable to the pipe 24 mounted on the pipe holder 22by a guide member 25 fixedly supported on the base 21 while slidinglymovable back and forth of the apparatus 10. In the embodiment shown inFIG. 1, the encasing tube 23 and the pipe 24 constitute a primary partof the enclosing means of this invention.

In the embodiment shown in FIG. 1, the encasing tube 23 has a hollowportion 23 a formed at a forward portion of the tube 23 and openedforward, and a solid base end portion 23 b integrally formed with thehollow portion 23 a. The base end portion 23 b is continued from thehollow portion 23 a and blocks a rear end of the hollow portion 23 awith a base end thereof linked to the operation mechanism 30. The hollowportion 23 a of the encasing tube 23 is adapted to accommodate a bossportion 5 constituting part of the sub insertion portion 4 of thegrommet 1, and a bundle of wirings W protruding rearward from the bossportion 5 so as to encase the boss portion 5 and its vicinity whilesecuring an airtight state of the boss portion 5, which will bedescribed later in a section regarding a test. The sealing unit 20 ischangeable between a test position in which the encasing tube 23sealably encases the boss portion 5 of the sub insertion portion 4 incooperation with the pipe 24 and a release position in which the grommet1 is released for detachable mounting by being drivingly moved back andforth by the operation mechanism 30 which is described in the nextsection.

In the embodiment shown in FIG. 1, the operation mechanism 30 includes atoggle lever mechanism. The operation mechanism 30 is equipped with arod 31 projecting from a rear end surface of the encasing tube 23. Arear end portion of the rod 31 is connected to a frontal end portion ofeach one a pair of arm members 36 to be pivotable about an axis of apivotal pin 36 a. A rear end portion of each one of the arm members 36is connected to an intermediate portion of a link member 37 a fixed toan operation handle 37 to be pivotable about a common axis of a pivotalpin 38. The operation handle 37 is a lever made of a metallic material.A grip portion 37 b is formed at one end portion of the operation handle37 for an operator to manipulate the apparatus by gripping. The oppositeend portion of the operation handle 37 is pivotally supported on a pairof brackets 39 fixed to a rear end portion of the base 21 to bepivotable about an axis of a pivotal pin 39 a by way of the link member37 a. The pivotal pin 39 a has a certain length in a transversedirection of the apparatus 10. With this arrangement, when an operatorgrips the grip portion 37 b of the operation handle 37 and pivotallyrotates the operation handle 37 about the axis of the pivotal pin 39 a,the encasing tube 23 is movable toward and away from the pipe holder 22by way of the link member 37 a, the arm members 36, and the rod 31. Inthe embodiment shown in FIG. 1, the apparatus is so designed thatpivotally rotating the operation handle 37 counterclockwise in FIG. 1retracts the encasing tube 23 away from the pipe holder 22, whereaspivotally rotating the operation handle 37 clockwise in FIG. 1 moves theencasing tube 23 toward the pipe holder 22.

Next, the air checker 40 is described. The air checker 40 includes aflow meter 42 provided inside a box member 41, and a judging section 43electrically connected to the flow meter 42.

The flow meter 42 includes an air feed pipe 42 a for feeding air at acertain pressure from an unillustrated pressurized air supply sourcethrough a regulator, an air eject pipe 42 b for ejecting the pressurizedair fed from the air feed pipe 42 as air for testing, and a float 42 cwhich is arranged in an air passage connecting the pipes 42 a and 42 band moves up and down depending on an air flow rate through the airpassage. With this arrangement, an operator is enabled to read thevertical position of the float 42 c through a transparent scale 42ddisposed in front of the flow meter 42. The air eject pipe 42 b iscommunicated with the hollow portion 23 a of the encasing tube 23 by aconnecting pipe 44.

The judging section 43 includes a PASS lamp 43 a indicating that agrommet has passed the test and a FAILURE lamp 43 b indicating that agrommet has failed the test, and is configured in such a manner thateither one of the lamps 43 a and 43 b is selectively turned on based ona signal output from the flow meter 42.

In the apparatus shown in FIG. 1, in the case where the flow rate iszero, the float 42 c is lowered to a lowermost position, and the PASSlamp 43 a is turned on, unless otherwise, the float 42 c is floatinglymoved upward, and the FAILURE lamp 43 b is turned on.

Next, a test procedure by the apparatus in accordance with theembodiment is described with reference to FIGS. 1, and 3 through 5.FIGS. 3 and 4 are partially plan views each illustrating a testprocedure to be implemented by the apparatus in accordance with theembodiment shown in FIG. 1. FIG. 5 is an enlarged sectional view showingessential parts of the apparatus in accordance with the embodiment shownin FIG. 1 at the time of testing.

The test procedure is described with reference to FIG. 1. First, anoperator tilts the operation handle 37 of the operation mechanism 30provided in the sealing unit 20 rearwardly downward to retract theencasing tube 23 away from the pipe holder 22 so as to shift the sealingunit 20 from the position shown in FIG. 1 to a release position wherethe encasing tube 23 is away from the pipe holder 22 (see FIG. 3).

Next, referring to FIG. 3, the operator holds the boss portion 5 thatconstitutes a part of the sub insertion portion 4 of the grommet 1 in astate that the boss portion 5 faces the rear side of the sealing unit 20so as to mount the grommet 1 onto the sealing unit 20 in the releasestate, and inserts the front end portion of the wiring bundle W that haspassed through the sub insertion portion 4 into the pipe 24 detachedfrom the pipe holder 22. Thereafter, the operator mounts the pipe 24onto the pipe holder 22 and accommodates the rear end portion of thepipe 24 in the encasing tube 23. Subsequently, the operator tilts theoperation handle 37 forwardly downward to move the tube 23 forward so asto sealably encase the sub insertion portion 4.

The sealing process is described referring to FIG. 5. Moving the tube 23close to the pipe 24 located in a forward position of the apparatus 10enables to set the hollow portion 23 a of the tube 23 opposingly andgenerally flush with the pipe 24 in a state that the grommet 1 ispressingly held therebetween. The inner diameter d1 of the pipe 24 isset larger than the outer diameter D2 of the tube 23. In thisarrangement, the sub insertion portion 4 of the grommet 1 is sealablyaccommodated in the hollow portion 23 a of the tube 23 in a state that asurrounding of the boss portion 5 is rendered into an airtight state.

In the above state, ejecting pressurized air set at a certain pressureinto the encasing tube 23 by the flow meter 42 enables to perform a teston a waterproof state of the sub insertion portion 4.

In the case where the sub insertion portion 4 is in a good waterproofstate, the air fed inside the tube 23 does not leak outside of the tube23. Accordingly, after the air pressure inside the tube 23 reaches acertain level, no more air is fed into the tube 23. As a result, theflow meter 42 indicates a flow rate at zero, and the PASS lamp 43 a ofthe judging section 43 turns on. On the other hand, in the case wherethe sub insertion portion 4 is not in a good waterproof state, the airleaks through a poorly sealed portion of the sub insertion portion 4,and accordingly, the flow rate of the flow meter 42 does not fall belowa certain level. As a result, the FAILURE lamp 43 b of the judgingsection 43 keeps turning on.

After the test, the operator returns the operation handle 37 to apredetermined position so as to set the sealing unit 20 to a releaseposition, and dismounts the grommet 1 according to a procedure in areverse manner to the procedure of mounting the grommet 1.

As mentioned above, in the foregoing embodiment, introducing air fortesting into the hollow portion 23 a of the tube 23 enables to test awaterproof state of the sub insertion portion 4. Thereby, sealabilitycorresponding to a waterproof state of the sub insertion portion 4 ofthe grommet 1 can be checked precisely, and waterproof performance ofthe grommet 1 can be verified easily.

Particularly, in this embodiment, the inner diameter d1 of the pipe 24is set larger than the outer diameter D2 of the encasing tube 23. Thisarrangement enables to provide the grommet 1 disposed between the tube23 and the pipe 24 with a resiliently wavy configuration in cooperationwith the arrangement that the end surface of the pipe 24 is set close tothe end surface of the tube 23 in a state that the pipe 24 is setgenerally flush with the tube 23. Thus, sealability between the grommet1, and the tube 23 and the pipe 24 which constitute the enclosing meansof this invention is improved, thus enabling to perform a test on awaterproof state of the grommet 1 with high precision.

The aforementioned embodiment is merely an example of this invention.This invention is not limited to the foregoing embodiment.

For instance, the pipe 24 and the tube 23 constitute the enclosing meansin the embodiment of this invention. Alternatively, the enclosing meansmay adopt the structure shown in FIG. 6. FIG. 6 is a sectional viewshowing an altered arrangement of the enclosing means.

As shown in FIG. 6, an annular groove G1 may be formed in an end surfaceof a pipe 24 or a tube 23 facing each other, whereas an annular rib G2may be formed on a corresponding end surface of the pipe 24 or the tube23 in such a manner that the annular groove G1 and the annular rib G2are engaged with each other. In this case, the engagement of the annulargroove G1 and the annular rib G2 provides further sealability betweenthe pipe 24 and the tube 23.

As a further altered arrangement of the enclosing means, an arrangementshown in FIGS. 9 through 12 may be provided.

The enclosing means as the further altered arrangement includes anencasing tube 53 for sealably enclosing an end portion of a subinsertion portion 4 of a grommet 1, and a pipe 54 opposing to the tube53 with respect to the sub insertion portion 4.

As shown in FIG. 9, the encasing tube 53 is a cylindrical member that isconcentrically connectable to the pipe 54 mounted on a pipe holder 52 bya guide member 25 fixedly supported on a base 21 while slidingly movableback and forth of the apparatus.

As shown in FIG. 11, the encasing tube 53 has a hollow portion 53 aformed at a forward portion of the tube 53 and opened forward, and abase end portion 53 b integrally formed with the hollow portion 53 a.The base end portion 53 b is continued from the hollow portion 53 a andblocks a rear end of the hollow portion 53 a with a base end thereoflinked to an operation mechanism 30. The hollow portion 53 a of the tube53 is adapted to accommodate a boss portion 5 constituting part of thesub insertion portion 4 of the grommet 1, and a bundle of wirings Wprotruding rearward from the boss portion 5 so as to encase the bossportion 5 and its vicinity while securing an airtight state around theboss portion 5.

The encasing tube 53 is changeable between a test position in which thetube 53 in cooperation with a pipe 54 sealably encases the boss portion5 of the sub insertion portion 4 and a release position in which thegrommet 1 is released for detachable mounting by an operation mechanismsimilar to the operation mechanism shown in FIG. 1.

The pipe holder 52 is described with reference to FIG. 9. The pipeholder 52 is a block member made of a resin. The pipe holder 52 has anupright position and is provided transversely in the middle part of thebase 21 at a frontal end portion thereof A groove (housing portion) 52 ais formed in an upper part of the pipe holder 52. The pipe 54 isdetachably mounted in the housing portion 52 a. A shoulder part 52 bagainst which a frontal surface of the pipe 54 is abutted is formed at afront end of the housing portion 52 a to keep the pipe 54 fromdisengaging from the pipe holder 52.

The pipe 54 is a hollow cylinder made of a resiliently deformable resinor its equivalent. The pipe 54 has a generally C-shape in cross sectionwith a slit 54 a extending longitudinally in the pipe 54. Preferably,the pipe 54 may be made of a relatively soft material such as polyvinylchloride (PVC). As shown in FIG. 12A, a pair of operative rods 55 areprovided in a state that the operative rods 55 extend radially outwardlyfrom the outer peripheral wall of the pipe 54 symmetrically with respectto the slit 54 a. The operative shafts 55 define a V-shape viewed from afront direction of the apparatus. Manipulating the operative rods 55enables an operator to openably close the slit 54 a with a less externalforce.

As shown in FIG. 11, in the modification, the outer diameter D3 of thepipe 54 is set smaller than the inner diameter d4 of the encasing tube53 when the pipe 54 resiliently reduces its diameter to close the slit54 a at the time of testing. Such a dimensional arrangement enables totightly hold the grommet 1 between the pipe 54 and the tube 53 bypressing a lead end portion 54 b of the pipe 54 against an innerperipheral end 53 c of the encasing tube 53.

Specifically, shifting the encasing tube 53 to a testable state whiledosing the slit 54 a by resilient deformation of the pipe 54 of theenclosing means as shown in FIG. 12B and interposing the grommet 1between the tube 53 and the pipe 54 enables to place the grommet 1 in acertain squeezed state between the pipe 54 and the tube 53 by pressingabutment of the lead end portion 54 b of the pipe 54 against the innerperipheral end 53 c of the encasing tube 53. The dimensional relationbetween the inner diameter of the pipe 54 and the outer diameter of theencasing tube 53 is optimally settable as long as sealability betweenthe grommet and the enclosing means at the time of testing is secured.

In the above arrangement, as shown in FIG. 9, in the case where the subinsertion portion 4 of the grommet 1 is tested, an operator places thepipe 54 into the housing portion 52 a of the pipe holder 52 in a statethat the slit 54 a is opened. Then, the operator places a wiring bundleW that has passed through the sub insertion portion 4 of the grommet 1inside the pipe 54 through the slit 54 a as shown in FIG. 10. Next, theoperator manipulates the operative rods 55 in the directions S, Srespectively, as shown in FIG. 12A, to resiliently deform the pipe 54,and then, closes the slit 54 a as shown in FIG. 12B. Subsequently,drivingly moving the tube 53 forward by an operation mechanism similarto the operation mechanism shown in FIG. 1 enables to hold the grommet 1between the pipe 54 and the tube 53 in a state that the lead end portion54 b of the pipe 54 is pressed against the inner peripheral end 53 c ofthe tube 53. This arrangement secures high sealability between thegrommet and the enclosing means, and enables the apparatus to perform atest on a waterproof state of the grommet with high precision.

Further, forming the slit 54 a in the pipe 54 facilitates mounting thesub insertion portion 4 of the grommet 1 on the apparatus, therebyimproving operability of the apparatus. This arrangement is advantageousin the case where passing a connector 8 through the pipe 54 forinsertion of a wiring bundle W is disabled because the connector 8connected to a terminal at an end portion of the wiring bundle W has anouter configuration larger than the inner diameter of the pipe 54.

As an altered form, as shown in FIG. 13, there may be provided a simpleconstruction in which a pipe 54′ is fixed to a pipe holder 52′ by a bolt56 with a slit 54′ opened upward in place of the arrangement shown inFIG. 9 in which the pipe 54 and the pipe holder 52 constitute theenclosing means.

In the foregoing embodiment and modifications, the apparatus enables totest a waterproof state of the sub insertion portion by sealablyenclosing an end portion of the sub insertion portion of the grommet bythe enclosing means and by feeding air for testing to the enclosingmeans.

As mentioned above, a judgment as to whether the grommet has passed thetest is determined based on the flow rate of air fed to the enclosingmeans so as to judge whether the grommet is in a good waterproof statedepending on the status of air fed to the enclosing means.Alternatively, a judgment may be made in water so as to determinewhether the supplied air leaks outside of the enclosing means.

As mentioned above, the arrangement in which the enclosing means isconstructed by the encasing tube for encasing the end portion of the subinsertion portion and a pipe opposing the encasing tube with respect tothe sub insertion portion, and the pipe has the inner diameter largerthan the outer diameter of the encasing tube enables to provide thegrommet with a wavy configuration when the grommet is interposed betweenthe encasing tube and the pipe. This arrangement improves sealabilitybetween the grommet and the enclosing means composed of the encasingtube and the pipe, and enables the apparatus to perform a test on awaterproof state of the grommet with high precision.

Furthermore, according to another aspect of this invention, theenclosing means includes the encasing tube for encasing the one endportion of the sub insertion portion and the pipe opposing the encasingtube with respect to the sub insertion portion. The pipe is formed witha longitudinally extending slit and has a generally C-shape in crosssection. With this arrangement, resiliently deforming the pipe to openand close the slit enables to place a wiring bundle that has passedthrough the sub insertion portion of the grommet into the pipe throughthe slit of the pipe. This arrangement facilitates mounting the subinsertion portion of the grommet onto the apparatus and improvesoperability of the apparatus. This arrangement is advantageous in thecase where passing a connector through a pipe for insertion of a wiringbundle is disabled because a terminal at an end portion of the wiringbundle has an outer configuration larger than the inner diameter of thepipe.

According to still another aspect of this invention, pressingly mountingthe grommet between the encasing tube and the pipe by resilientlyreducing the diameter of the pipe in a state that the slit is closedsecures sealability between the grommet and the enclosing means composedof the encasing tube and the pipe. This arrangement enables theapparatus to perform a test on a waterproof state of the grommet withhigh precision.

Preferably, the enclosing means of this invention includes a tube with aclosed end at one end thereof to receive the one end portion of the subinsertion portion, and a hollow cylinder for pressingly sandwiching thesub insertion portion with the tube.

Preferably, the tube and the hollow cylinder are so designed as topressingly sandwich the grommet therebetween in such a manner that thegrommet is formed with a wavy configuration.

Preferably, the tube may tightly hold the grommet in a state that aflange portion of the grommet presses an inner peripheral end thereof.

The enclosing means may preferably include a holder for detachablyholding the hollow cylinder.

Preferably, an inner diameter of the tube is set larger than an outerdiameter of the hollow cylinder, or vice versa.

The hollow cylinder may include a resilient member of a C-shape in crosssection for resiliently opening and closing a slit to encase a wiringbundle of a grommet.

Preferably, the hollow cylinder may be fixed concentrically with thetube and opposing thereto while the slit is closed.

Preferably, the hollow cylinder may include a pipe made of a resin.

It should be appreciated that a variety of modifications and alterationsare applicable as long as such modifications and alterations do notdeviate from the scope of claims of this invention.

EXPLOITATION IN INDUSTRY

According to this invention, a test as to whether a sub insertionportion is in a good waterproof state can be performed by introducingair for testing to enclosing means. In this arrangement, sealabilitycorresponding to a waterproof state of the sub insertion portion of agrommet can be checked precisely. Thus, an operator can verifywaterproof performance of the grommet easily.

What is claimed is:
 1. An apparatus for testing a waterproof state of asub insertion portion of a grommet provided with a flange portionmountable on a vehicle body, a main insertion portion formed on theflange portion to insert a bundle of wirings, and the sub insertionportion provided eccentrically on the grommet relative to the maininsertion portion, comprising: enclosing means for sealably enclosingonly an end portion of the sub insertion portion provided eccentricallyon the grommet; air feeding means for feeding air for testing to a spacein which the sub insertion portion is sealably accommodated; and judgingmeans for judging whether the sub insertion portion is in a goodwaterproof state based on a status of the air fed from the air feedingmeans.
 2. The apparatus according to claim 1, wherein the enclosingmeans includes a tube with a bottom which encases an one end portion ofthe sub insertion portion and a hollow cylinder which pressingly pinchesthe sub insertion portion with the tube.
 3. The apparatus according toclaim 2, wherein the tube and the hollow cylinder pinch the grommettherebetween in such a manner as to form a wavy configuration on thegrommet.
 4. The apparatus according to claim 2, wherein the tube isadapted to encase the grommet in such a manner that the flange portionof the grommet is pressed against an inner peripheral end at one end ofthe tube.
 5. The apparatus according to claim 2, wherein the enclosingmeans includes a holder for detachably holding the hollow cylinder. 6.The apparatus according to claim 2, wherein one of the tube and thehollow cylinder has an inner diameter larger than an outer diameter ofthe other one.
 7. The apparatus according to claim 2, wherein the hollowcylinder includes a resilient member of a C-shape in cross section, theresilient member being formed with a slit for receiving the wiringbundle of the grommet therein and having such a configuration as toresiliently open and close the slit.
 8. The apparatus according to claim7, wherein the hollow cylinder is fixed concentrically with the tube andopposing thereto when the slit is dosed.
 9. The apparatus according toclaim 7, wherein the hollow cylinder is a pipe made of a resin.
 10. Theapparatus for testing a waterproof state of a sub insertion portion of agrommet according to claim 1, wherein said enclosing means comprises: afirst member and a second member, said first and second members beingconfigured to sealably enclose only an end portion of the sub insertionportion provided eccentrically on the grommet, wherein one of said firstmember and said second member includes a recess that accommodates a wirebundle inserted in the sub insertion portion.
 11. An apparatus fortesting a waterproof state of a sub insertion portion of a grommetprovided with a flange portion mountable on a vehicle body, a maininsertion portion formed on said flange portion to insert a bundle ofwires, said sub insertion portion eccentrically provided in relation tosaid main insertion portion, comprising: an enclosure configured tosealingly enclose only an end portion of said sub insertion portioneccentrically provided in relation to said main insertion portion; anair feeder configured to feed air for testing to a space in which saidsub insertion portion is sealingly accommodated; and a judging apparatusconfigured to determine whether said sub insertion portion is in awaterproof state, based on a status of the air fed from said air feeder.12. The apparatus according to claim 11, wherein said enclosurecomprises: a tube with a bottom configured to encase an end portion ofsaid sub insertion portion; and a hollow cylinder configured topressingly pinch said sub insertion portion with said tube.
 13. Theapparatus according to claim 12, wherein said tube and said hollowcylinder pinch said grommet therebetween to substantially form a waveconfiguration on said grommet.
 14. The apparatus according to claim 12,wherein said tube is configured to encase said grommet such that saidflange portion of said grommet is pressed against an inner peripheralend at one end of said tube.
 15. The apparatus according to claim 12,wherein said enclosure comprises a holder for detachably holding saidhollow cylinder.
 16. The apparatus according to claim 12, wherein one ofsaid tube and said hollow cylinder has an inner diameter larger than anouter diameter of the other of said tube and said hollow cylinder. 17.The apparatus according to claim 12, wherein said hollow cylindercomprises a resilient member having a substantially C-shaped crosssection, said resilient member comprising a slit configured to receivethe bundle of wires of said grommet therein, said slit furtherconfigured to resiliently open and close.
 18. The apparatus according toclaim 17, wherein: said hollow cylinder is configured to beconcentrically arranged with said tube; and said hollow cylinder andsaid tube are configured to be arranged opposite each other when saidslit is closed.
 19. The apparatus according to claim 17, wherein saidhollow cylinder is made of a resin.
 20. The apparatus for testing awaterproof state of a sub insertion portion of a grommet according toclaim 10, wherein said enclosure comprises: a first member and a secondmember, said first and second members being configured to sealinglyenclose only an end portion of the sub insertion portion eccentricallyprovided in relation to said main insertion portion, wherein one of saidfirst member and said second member includes a recess that accommodatesa wire bundle inserted in the sub insertion portion.